Scientists Discuss Pebble Watershed Risks in Public Session

The U.S. Environmental Protection Agency today (Wednesday) wrapped-up the public portion of its scientific "Peer Review" of the proposed Pebble Mine.

Twelve scientists will spend the next few months -- in closed-door sessions -- gathering information that will eventually allow the agency to determine whether Pebble can be operated in compliance with the "Clean Water Act of 1972."

The Bristol Bay Fishermen -- and Alaska Natives --  who brought the E.P.A. Into the decision process allege that Alaska State authorities have never blocked a major mine project in the history of the state. It's an allegation that a Alaska Department of Natural Resources officer today denied.

Whatever the case, the fact is that the E.P.A. Has the power to single-handedly shut-down Pebble before it ever gets started. That's why the Fishermen and Tribal Groups from Bristol Bay say they sought the intervention of a federal agency.

The fact is, E.P.A. has "veto power" over Pebble.
 
E.P.A. has only invoked that veto 13 times in its entire history. Just last year the agency denied a coal company -- in West Virginia -- permission to perform "Mountain Top Removal" as an economical way to get coal out of a seam. "Mountaintop Removal" is the name given to a process in which the peak of a mountain is dynamited -- to get at the coal -- and the resulting waste rock is poured into streams at the mountain's base.

The E.P.A. Ruled that such a process would constitute a violation of the Clean Water Act, and so refused to issue a permit for it. Environmental groups in Alaska are hoping that the E.P.A. will make a similar ruling with regard to Pebble.

Pebble still has filed no final development plan with the state of Alaska, so the E.P.A. is examining a hypothetical mine that might be used to the huge amounts of copper, gold and molybdenum known to exist at the so-called "Pebble deposit" near Lake Iliamna.

The agency says that in its most massive development scenario, 10 billion tons of ore would be removed from the Pebble Deposit over an operational period of about 1 century.

If the entire ore deposit is mined, it would make Pebble one of the largest mines in North America. In fact, Pebble alone would be larger than every other hard-rock mine in Alaska put together.

The Pebble Limited Partnership is unhappy with the vast scale of the mining portrayed in the E.P.A.'s preliminary Watershed Assessment report. Pebble C.E.O. John Shively points out that he is only looking to permit a 25-year mine. Scenarios that would mine all 11 billion tons of commercial-grade ore would require four times as long.

But the E.P.A. points out that once mining begins, and infrastructure such as slurry pipelines and roads are put in place, Pebble will begin to see economies of scale that make mining the entire deposit over the course of the next century an increasingly attractive proposition. 

There are an estimated $500 billion worth of copper, gold and molybdenum beneath Pebble. Obviously, it's a huge sum -- and it gives a sense of just what's at stake.

At any rate, the scientists impanelled by E.P.A. are assuming that a very large mine might be built -- and it was clear they understood fully the magnitude of their task.

One of their main concerns is this: The residue of mining, known as mine tailings, remain toxic indefinitely. The E.P.A. says those tailings will have to be sequestered from the environment "in perpetuity."

Which raises the question: What, exactly, does "in perpetuity" mean? The E.P.A. document only reads "centuries or more."

Today the scientists tried to define it more precisely. "We've estimated the tailings will produce acid drainage anyhwere from 10 to 40 thousand years," said Dr. John Stednick. It's a stunning figure attached to a sobering environmental issue. When water passes over ground-up rocks from mines, it mixes with sulfur in the rock powder and becomes acidic. 

The problem with such "acid drainage" is that it is toxic to fish. The acids can leach heavy metals -- essentially poison -- from the billions of tons of waste rock, or tailings that are left at the abandoned mine site. And it's been proven, said one of the scientists, "some very low concentrations of copper --  a just a few micrograms per liter, then can have an impact on olfaction (the sense of smell) of salmon."